yeah it says its missing an application to open it :(((((
just in case you don’t see the reply I’ll put it here again, but I found a way to make it work, you have to open the Terminal, type chmod +x (leave a space after +x), then drag the TheFalseSun file that is in the The False Sun.app > Contents > MacOS into the Terminal window and press Enter. After that, try launching the game again. This fixed the problem for me!